$$\lim_{x \rightarrow \pi+}\sec2x$$
is it positive or negative?

Question

$$\lim_{x \rightarrow \pi+}\sec2x$$
is it positive or negative?

empty · Answer

Any ideas? Where are you stuck?

tkhunny · Answer

Is the cosine positive or negative in the neighborhood of $\pi$?

anonymous · Answer

I don't know I just cant't grasp the concept.

anonymous · Answer

this is one part of calculus I am just struggling with

empty · Answer

Explain what you do understand and I can help you understand and fill in the gaps if you want to learn.

anonymous · Answer

When its on the graph i can get it but my teacher doesn't want us using a graph

anonymous · Answer

usually I can solve backward when I don't understand it

tkhunny · Answer

Come on...

$\cos(\pi) = -1$
$\cos(2\pi) = +1$

What do we know about $\sec(2\pi)$?

anonymous · Answer

i have class but I will tr again later. hopefully It will help when i log back on

empty · Answer

@Clare12 Well you are trying to run before you can walk if you don't use graphs. You need to spend more time visualizing roughly what trigonometric graphs look like with several common values such as $\pi$ or $\frac{\pi}{2}$ and others.